LOS ANGELES – If things don’t go Ricardo Mayorga’s way on May 15, his MMA career could be over before it ever really starts.

Mayorga, who faces Din Thomas (25-8 MMA) in a 160-pound catchweight main event at “Shine Fights: Worlds Collide” on Saturday, May 15, said he’ll retire from MMA if he loses – or even if he wins by decision.

If he wins as he predicts – a knockout in the first minute of the first round – he’ll call out boxing kingpin Floyd Mayweather.

“(Felix) Trinidad, (Shane) Mosely, (Oscar) De La Hoya – combined, they’ve had more than six belts,” Mayorga (28-7 Boxing, 0-0 MMA) today told MMAjunkie.com (www.mmajunkie.com) through translator Steve Freitxas. “I’ve only lost to those big champs. But I’m not going to lose to a nobody.”

The boxer and the MMA veteran nearly came to blows at a New York press conference in April when Mayorga karate-chopped Thomas’ neck in the midst of a trash talk session. They were far more cordial today at a small gathering of reporters in a West Los Angeles boxing gym.

Mayorga, a native of Managua, Nicaragua, threw a few jibs at Thomas in Spanish during a photo op in the middle of the ring, to which Thomas replied, “Yo quiero cerveza,” (“I want beer”) to laughs all around.

The tough-talking former boxing champ said his early streetfighting days prepared him for next Saturday’s MMA fight.

“I used to fight raw in the streets, brawling,” he said “They used to kick you in the face while you’re down on the ground. On the street, they hit you with shoes; they hit you with everything.”

Rosendo Alvarez, Mayorga’s boxing trainer of three years, said his fighter had been training MMA techniques for two months with a private teacher at The Fight Club in Miami. He and Mayorga declined to name the trainer but said the training focused on “mostly defensive tactics.”

“At 160 (pounds), he won’t be starved,” Alvarez said. “It’s not like he’s going to fight Mayweather, and he’s got to drop down to 143 (pounds), it’s a huge difference. He’s got real power with his punches. That’s where I think Din Thomas messed up, … taking the fight at 160 instead of a lower weight.”

Mayorga said he has long been a fan of MMA for its “violence” and would have chosen the sport over boxing had it been popular when he started fighting at age 13.

“It was really tough to get ahold of somebody for me to jump into MMA,” he said. “But now that I’m getting the opportunity, I want to embrace it.”

In the ring, Mayorga has hit hard times. The hard-chinned slugger was knocked out by former champion Shane Mosley in the 12th round of his most recent fight nearly two years ago. He has lost four of his past seven fights, including those he mentioned.

Most memorably, he suffered a sixth-round TKO loss to Oscar De La Hoya in May 2006 after a protracted trash-talk campaign.

Despite the bad streak, Mayorga brushed off criticism that he’s trying MMA because he can’t compete with upper-echelon boxers. He said a boxing title match in Germany is in the works after the Thomas fight.

“After I beat Din, I’m going to call out Mayweather,” he said.

He doesn’t believe he’s putting the boxing match in jeopardy.

“I’m not going to be running around the ring,” Mayorga said. “I’m going to put up a good fight, and I’ll be back to boxing as well.”

Thomas, a former UFC lightweight contender, has won three-consecutive MMA fights since his release from the Las Vegas-based promotion in 2008.

That didn’t keep Mayorga from trampling on his opponent’s reputation.

“He’s the most ridiculous one from [American Top Team],” Mayorga said of Thomas. “Everybody that trains out of ATT is a several-time champion, and [Din] has never been a champion. He’s got a little pre-kindergarten belt.

“I’m going to be happy I got into MMA but not very happy because I beat Din Thomas, because he’s basically a nobody. I want a real champ.”

Mayorga promises to show fight fans that boxers can fight in MMA. Anything less, and he’ll throw in his four-ounce gloves.

“I come from a poor neighborhood, from the streets, and I’m ready to fight,” he said.

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